The coronavirus second wave is spreading more quickly than the first outbreak in spring, a top French scientist has warned, amid a growing resurgence of the virus across Europe.

"The virus is circulating more quickly... the resurgence of the pandemic started in August," French government scientific adviser Arnaud Fontanet told BFM TV on Friday.

He said France had managed to bring the virus under control by the end of the June, and because the number of people being taken to hospital remained low until the end of August, authorities were given a false sense of security despite cases already going up at the time.

"And then there was one cold week in September and all the indicators went the wrong way again all over Europe. The virus spreads better in the cold because we live more inside," said the epidemiologist.

"We have a lot of tools to protect ourselves against the virus but we're facing a difficult period," he added, echoing Prime Minister Jean Castex, who warned of a "tough November" as the French government extended a curfew imposed last week on Paris and eight other cities to dozens more areas.

The 9pm to 6am curfew comes into force at midnight tonight and 46 million people - almost two-thirds of the country's 67 million population - will be affected.

"A second wave of the coronavirus epidemic is now under way in France and Europe. The situation is very serious," Mr Castex said at a news conference.

On Thursday, the country reported a record 41,622 new confirmed cases of COVID-19.

The national figure now stands at more than one million infections, and more than 34,200 people have died, according to Johns Hopkins University which has been tracking the outbreak.

Countries across Europe, like in the UK, are returning to restrictive measures following a surge in cases.

Belgium, one of the worst-hit countries in Europe, further tightened restrictions on social contacts on Friday, banning fans from sports matches, limiting the number of people in cultural spaces and closing theme parks.

Although infection rates in Germany have been much lower than other COVID hotspots in Europe, cases have been accelerating and hit a record 11,247 on Thursday.

Across Europe, 20 countries set new daily case records on Wednesday, including the UK, which saw a rise of 26,688.

The Czech Republic, which is seeing Europe's biggest surge in COVID-19 cases, has ordered most shops and services to close to curb the spread of the virus.

The Netherlands has also returned to partial lockdown, closing bars and restaurants, but kept schools open.

And Spain became the first country in western Europe this week to record one million coronavirus cases - doubling its tally in just six weeks.